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To calculate the size of a folder in C#, you need to traverse through all files in the folder and its subdirectories, then sum up their sizes. The DirectoryInfo class provides methods to enumerate files and directories, making this task straightforward. Syntax Following is the syntax for getting folder information and enumerating files − DirectoryInfo info = new DirectoryInfo(@"C:\FolderPath"); long size = info.EnumerateFiles("*", SearchOption.AllDirectories).Sum(file => file.Length); Using DirectoryInfo for Simple Folder Size The most basic approach uses DirectoryInfo.EnumerateFiles() with SearchOption.AllDirectories to include all subdirectories − using System; using System.IO; using System.Linq; ... Read More
The StringTemplate class is part of the NString library that provides enhanced string formatting capabilities in C#. It offers a more readable alternative to String.Format by using named placeholders instead of numbered ones, making code less error-prone and easier to maintain. The StringTemplate class comes with the NString library, which includes several useful extension methods for string manipulation such as IsNullOrEmpty(), IsNullOrWhiteSpace(), Join(), Truncate(), Left(), Right(), and Capitalize(). Syntax The basic syntax for StringTemplate.Format uses named placeholders − string result = StringTemplate.Format("{PropertyName}", new { PropertyName = value }); For formatting with specific format ... Read More
The Where method in LINQ is used to filter elements from a collection based on a specified condition (predicate). It returns a new IEnumerable containing only the elements that satisfy the given criteria. Syntax The Where method has two overloads − // Filter based on element value only public static IEnumerable Where(this IEnumerable source, Func predicate) // Filter based on element value and index public static IEnumerable Where(this IEnumerable source, Func predicate) Parameters source − The input sequence to filter predicate − A function that tests each element for a condition ... Read More
In C# inheritance, when creating objects of derived classes, the base class constructor is called first, followed by the derived class constructor. This ensures that the base class is properly initialized before the derived class adds its own functionality. The derived class inherits member variables and methods from the base class. When instantiating a derived class object, you can use the base keyword to explicitly call the base class constructor and pass required parameters. Syntax Following is the syntax for calling a base class constructor from a derived class − public class DerivedClass : BaseClass ... Read More
The Dictionary.Item[] property in C# provides a convenient way to get or set values in a Dictionary using indexer syntax. This property allows you to access dictionary values directly using square bracket notation with the key, similar to array indexing. Syntax Following is the syntax for the Dictionary.Item[] property − public TValue this[TKey key] { get; set; } Parameters key − The key of the element to get or set. Return Value The property returns the value associated with the specified key. If the key is not found when ... Read More
To calculate power of a number using recursion in C#, we use the mathematical principle that n^p = n × n^(p-1). The recursive function calls itself with a reduced power until it reaches the base case. Syntax Following is the syntax for a recursive power function − static long Power(int number, int power) { if (power == 0) { return 1; // base case } return number * Power(number, power - 1); // recursive ... Read More
Abstraction is a fundamental concept in object-oriented programming that focuses on hiding complex implementation details while showing only the essential features of an object. In C#, abstraction allows you to define what an object does without specifying how it does it. Abstraction and encapsulation work together − abstraction defines the interface and essential behavior, while encapsulation hides the internal implementation details from the outside world. Key Concepts of Abstraction Hide complexity − Users interact with simplified interfaces without knowing internal workings Focus on essential features − Only relevant methods and properties are exposed Provide common interface ... Read More
The File.Copy method in C# is used to copy an existing file from one location to another. This method is part of the System.IO namespace and provides a simple way to duplicate files programmatically. Syntax Following is the syntax for the File.Copy method − File.Copy(string sourceFileName, string destFileName); File.Copy(string sourceFileName, string destFileName, bool overwrite); Parameters sourceFileName − The path of the file to copy. destFileName − The path of the destination file. overwrite − Optional boolean parameter. If true, overwrites the destination file if it already exists. ... Read More
The nullable DateTime in C# allows you to assign null values to DateTime variables, which is useful when a date might not be available or applicable. This is particularly valuable in database operations where date fields can be NULL, or when dealing with optional date parameters. Syntax A nullable DateTime is declared using the question mark (?) syntax − DateTime? variableName = null; Alternatively, you can use the full Nullable syntax − Nullable variableName = null; Key Properties and Methods Nullable DateTime provides several useful properties and methods − ... Read More
The Dictionary.Keys property in C# is used to fetch all the keys in the Dictionary. This property returns a KeyCollection that contains all the keys from the dictionary, which can be iterated through using a foreach loop. Syntax Following is the syntax − public System.Collections.Generic.Dictionary.KeyCollection Keys { get; } Return Value The Keys property returns a Dictionary.KeyCollection containing all the keys in the dictionary. This collection is a live view of the keys, meaning if the dictionary changes, the collection reflects those changes. Using Dictionary.Keys Property Example Let us see ... Read More